Synergistic dewaxing and composition

ABSTRACT

A wax modifying composition comprising the combination of (1) a Friedel-Crafts condensation product of a halogenated paraffin with an aromatic hydrocarbon and (2) an oil soluble copolymer of ethylene and a C3-C30 alpha olefin, or a terpolymer of ethylene with a C3-C30 alpha olefin and a minor amount of a nonconjugated diolefin. The copolymer and terpolymer may be improved by oxidation to form hydroperoxy materials followed by reduction to form reduced oxygenated compounds.

llnited States t Henselman et a1.

SYNERGIS'MC DIEWAXHNG AND COMPOSITHUN Richard 0. lllenselman, NorthPlainfield; Herbert G. Bun-hard, Convent Station, both of NJ.

Assignee: Esso Research and Engineering (lompnny Filed: June 15, 1970Appl. No.: 46,557

inventors:

Related U.S. Application Data Continuation of Ser. No. 795,357, Jan. 30,1969, abandoned, which is a continuation-in-part of Ser. No. 539,326,Apr. 1, 1966, abandoned.

[ 1 ll eh. 1, 11972 [56] References Cited UNITED STATES PATENTS3,108,944 10/1963 Stoller ..208/33 3,239,445 3/1966 Leonard et al.......208/33 3,374,073 3/1968 Gergel ...44/62 3,388,977 6/1968 Burkard etal ..44/62 Primary Examiner-Herbert Levine 5 7] ABSTRACT A wax modifyingcomposition comprising the combination of (1) a Friedel-Craftscondensation product of a halogenated paraffin with an aromatichydrocarbon and (2) an oil soluble copolymer of ethylene and a C -Calpha olefin, or a terpolymer of ethylene with a C -C alpha olefin and aminor amount of a nonconjugated diolefin. The copolymer and terpolymermay be improved by oxidation to form hydroperoxy materials followed byreduction to form reduced oxygenated compounds.

9 Claims, No Drawings SYNERGISTIC DEWAXING AND COMPOSITIONCROSS-REFERENCES TO RELATED APPLICATIONS This application is acontinuation of application, Ser. No. 795,357 filed Jan. 30, 1969, whichin turn is a continuation-inpart of application Ser. No. 539,326 filedApr. 1, 1966, both applications now abandoned.

This application is a continuation-in-part of copending application,Ser. No. 539,326, filed Apr. l, 1966 now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the invention This inventionrelates to a novel dewaxing aid composition and to the utilization ofsame, and more particularly to a dewaxing aid comprising a combinationof additives which synergistically improve the separation of waxes frompetroleum oils.

2. Description of the Prior Art Various methods are known in the art forseparating wax from petroleum oil. One such method, for instance, ischilling the waxy oil and filtering off the solid wax. One of the mostpopular ways of dewaxing oils is known as solvent dewaxing. Thiscomprises diluting the oil with a solvent, heating until completesolution is obtained, and then chilling until the desired amount of waxhas crystallized out. The wax crystals thus formed are separated fromthe slurry by means of filtration. The wax is then further purified,while the solvent is recovered for reuse and the dewaxed oil is sent toother refinery processes.

Although such solvent dewaxing has largely replaced other processes forthe separation of wax from hydrocarbon oils, filtration of the waxcrystals from the slurry formed during dewaxing is difficult and oftenthe filtration rate of the slurry limits the capacity of the entireprocess. The slurry filtration rate is determined primarily by the sizeand shape of the wax crystals formed during the chilling step of theprocess. Very fine crystals tend to clog the filter media rapidlyreducing the filtration rate and eventually necessitating shutdown ofthe filters for removal of the accumulated wax. Very large crystals tendto form gellike interlocking masses which do not form a compact filtercake, which contain a large amount of oil and solvent, and which aredifficult to wash. As a solution to this problem, it has become thepractice in the art to incorporate in the wax-containing petroleum oilmaterials which modify the size and shape of wax crystals in such amanner as to permit more rapid separation of the wax during dewaxingoperations. These materials are known as dewaxing aids. For example, ithas been known for some time that Friedel-Crafts condensation productsof halogenated paraffins and aromatic hydrocarbons are effectivedewaxing aids for wax-containing petroleum oils. However, the continuedneed for more efficient petroleum dewaxing processes has raised therequirements of dewaxing and filtering aids. The provision ofnew andmore efficient dewaxing aids is, therefore, ofgreat importance to thepetroleum refining art.

SUMMARY OF THE INVENTION It has now been found, in accordance with thisinvention, that by incorporating in a petroleum oil, as dewaxing aids,the combination of (a) a conventional wax crystal modifier made by theFriedel-Crafts reaction, i.e., a condensation product of a halogenatedparaffin with an aromatic hydrocarbon and (b) a polymer comprisingethylene and C C alpha-olefins, a synergistic improvement in the waxcrystal characteristics of the oil over that provided by theincorporation of either of these two types of additives alone isobtained. It is, therefore, the primary object of this invention toprovide a new and highly improved class of dewaxing aids. Other andfurther ob jects ofthe invention will become apparent from the followingdetailed description thereof.

The present invention contemplates the employment of any conventionalwax crystal modifier (e.g., pour depressant,

dewaxing aid, etc.) made by the Friedel-Crafts condensation of ahalogenated paraffin with an aromatic hydrocarbon. The halogenatedparaffin may, for example, contain from about eight to about 30 carbonatoms, preferably from about It) to about 22, and from about 5 to about25 weight percent chlorine, preferably from about 10 to about 18 weightpercent. Typically, the halogenated paraffins used to prepare thiswell-known class of wax modifiers are themselves prepared bychlorinating to the aforedescribed chlorine content a paraffin waxhaving a melting point within the range between about 120 to about l F.The aromatic hydrocarbon used herein contains a maximum of threesubstituent groups and/or condensed rings and may be a hydroxy compoundsuch as phenol, cresol, xylenol, or an amine such as aniline, but ispreferably naphthalene, phenanthrene or anthracene. The Friedel-Craftscondensation products of the instant invention are prepared inaccordance with well-known techniques, e.g., British Pat. Nos. 51 1,207and 562,714.

The second general component of the instant invention is an oil-solublepolymer comprising ethylene and C -C alphaolefins. Theethylene-alpha-oleiin polymers which are opera ble in the concept ofthis invention have a number average molecular weight in the range fromabout 500 to about 50,000, preferably in the range of about 1,000 tol5,000. The amount of ethylene present as compared to the amount ofalpha-olefin present is in the range from about 5 to mole percent, thepreferred range being from 20 to 80 mole percent ethylene.

The alpha-olefins suitably employed in the instant invention include thesubstituted and unsubstituted monoalpha-olefins containing from three toabout 30 carbon atoms. The chains may be branched or unbranched and maycontain cyclic structures. It is preferred, however, that thealpha-olefin be substantially linear. Nonlimiting examples of operablealphaolefins include propylene, pentent-l, heptene-l, decene-l,dodeeene-l, hexadecene-l, octadecene-l, eicosene-l, docosene-l,petracosene-l, octacosene-l, triacontene'l, and the like.

The ethylene-alpha-olefin polymers suitably employed in the presentinvention may contain a third unsaturated monomer such as, for example,a bicyclic, alicyclic or aliphatic nonconjugated diolefin containingfrom about six to about 15 carbon atoms. The amount of third monomerpresent is in the range of from about 0.5 to 20 mole percent, preferablyfrom about 1 to about 7 mole percent based on the total amount ofethylene and alpha-olefin present. Nonlimiting examples of suitablemonomers include cyclopentadiene, methylene norbornene, hexadiene,dicyclopentadiene, tetrahydroxylindene, 5-vinyl-2-norbornene,2-methyl-norbornene, 2,4-dimethyl-2,7-0ctadiene, 3-methallylcyclopentane, tetradecene, and 3-(2-methyl-l-propene) cyclopentene andthe like.

Polymerization catalysts may or may not be used, i.e., in some instancesthe polymerization may be thermally initiated. In general, any of theconventional free radical catalysts may be used to effect polymerizationof the C -C alpha-olefins while Ziegler'type catalysts may be used topolymerize the C -,-C alpha-olefins. These Ziegler-type catalysts mayalso be used to polymerize the C C;,,, alpha-olefins of the invention.Among the useful free radical catalysts are benzoyl peroxide,tert.-butyl hydroperoxide, ditert.-butyl peroxide, cumene peroxide, andthe like. The Ziegler-type catalyst used generally consists of atransition metal halide such as titanium tetrachloride, vanadiumtetrachloride or vanadium oxytrichloride, and an aluminum alkyl compoundsuch as aluminum triethyl or aluminum diethyl chloride and the like. Thecatalyst, where used, may vary in concentration from about 0.1 to about5 percent by weight based on the reactants.

With further reference to the Ziegler-type catalysts, these catalystsare made of components of two types, namely, compounds of the heavytransition metals of groups IV, V, and Vi of the periodic systembeginning with titanium, vanadium, and chromium and organometalliccompounds and hydrides of metals of groups 1, 11, and 111 of theperiodic system wherein the amount of the compounds derived from a grouplV-Vl metal may range from 0.01 to 2.0 moles per mole of theorganometallic compound. The compounds of the first type are preferablyhalides, oxyhalides, or alcoholates, while titanium and vanadium deservepreference as metals. The second component is preferably anorganometallic compound of lithium, sodium, magnesium, or aluminum, inwhich the organic portions are preferably alkyl radicals. In theseorganometallic compound, the valence of the metal can be partiallysaturated by halogens or alkoxyls, provided, naturally, that at leastone bond binds the metal directly to a carbon atom. Mixtures of two ormore compounds of the type described above can often be used toadvantage.

Effective catalysts for polymerizing the monomers of the inventioninclude the following combinations: aluminum triisobutyl and vanadiumtrichloride; aluminum triisobutyl, aluminum chloride, and vanadiumtrichloride; vanadium tetrachloride and aluminum trihexyl; vanadiumtrichloride and aluminum trihexyl; vanadium triacetylacetonate andaluminum diethyl chloride; titanium tetrachloride and aluminum trihexyl,vanadium trichloride and aluminum trihexyl; titanium trichloride andaluminum trihexyl; titanium dichloride and aluminum trihexyl; etc.

Polymerization of the aforedescribed monomers is effected byconventional methods, e.g., U.S. Pat. Nos. 3,000,866, 3,093,621 and2,933,480. Ziegler-catalyzed polymerizations are generally effected byreacting the monomers at atmospheric pressure in a suitable solvent(e.g., hexane, heptane, octane and the like) in the presence ofacatalyst and at a temperature in the range within about to 50 C. for aperiod of from about 10 minutes to 3 hours. Free radical polymerizationsare typically effected by reacting the aforedescribed monomers in thepresence of a catalyst and a suitable solvent at a pressure within therange of about atmospheres to 1,000 atmospheres and a temperature withinthe range of about 50 to 300 C. for a period of about 4 to about 50hours. in addition, the polymerization may be thermally initiated byreacting the monomers at a temperature within the range of about 200 toabout 300 C.

While the aforedescribed ethylene-alpha-olefin polymers of the instantinvention may be utilized without further processing, it has been foundthat the effectiveness of these materials mayin some instances beimproved by oxidation to form hydroperoxy materials followed byreduction to form reduced oxygenated compounds. The oxidation of thesematerials is disclosed in a copending application, Ser. No. 423,870,filed Jan. 6, 1965 now U.S. Pat. No. 3,388,977. In general, theethylene-alpha-olefin copolymers and terpolymers may be oxidized to formthe hydroperoxy materials by any one of several methods. The polymersmay be oxidized in solution, or as a solid with an oxygen-containing gaswith or without a free radical initiator such as peroxides, azocompounds, or metal salts. An effective method of oxidizing the polymeris to dissolve from about 1 to 20 percent by weight in a hydrocarbondiluent such as heptane or benzene and to pass air or oxygen through thesolution at the desired temperature until oxidation of the requiredlevel is reached. The type of solvent is not critical to the invention.The polymer may also be oxidized as an emulsion or as a suspension inany fluid such as water. The solvent or suspending fluid need not beinert to oxidation under the conditions employed to oxidize thecopolymer. The temperature and pressure conditions will vary with thetype of solvent used for oxidation. Temperatures in the range of about45 to 250 C. and pressures in the range of about 0.5 to 100 atmospheresare satisfactory. The oxygencontaining gas is preferably passed throughthe polymer solution or suspension in excess. Free radical initiatorssuch as peroxides, hydroperoxides, azo compounds, diazo compounds,peresters, peracids, ozone, hydrogen peroxide, disulfides, persulfides,or hydrazines may be used in concentrations of about 0.001 weightpercent and higher. Metal salts well known in the art may also be usedto promote the oxidation.

Such compounds contain transition metal ions that are easily oxidizedand reduced. Examples are iron, cobalt, vanadium, cerium or manganesesalts. Soluble salts such as acetylacetonates or tallates of the metalsare preferred for the hydrocarbon solutions, while water-soluble saltssuch as chlorides are preferred for the emulsions.

The oxidized material is then reduced as follows: the oxidized material,while still in solution, or suspension or as a solid, is contacted witha reducing agent. Such a reducing agent should be capable of reactionwith oxidized groups on the polymer. Applicable methods include reactionwith sodium sulphite, lithium aluminum hydride, sodium borohydride,tertiary phosphines, triethyl phosphite, hydrazine hydrate, aluminumamalgam, alkaline sodium sulfide, hydriodic acid and zinc dust-aceticacid. Reaction with acids or alkali as well as thermal treatment mayalso remove active oxygen-containing groups from the oxidized polymer.Removal of these groups is desirable, since the polymer is less reactiveafter reduction and may be conveniently stored without further reactiontaking placed.

The product produced by the oxidation procedure is a soluble polymer oflower molecular weight than the starting polymer. The molecular weightdepends on the extent and conditions employed during the oxidation. Thenumber average molecular weight is in the range from about 500 to about50,000, wherein the amount of active oxygen before reduction is in therange from about 2 to 500 milliequivalents per g. of polymer asdetermined iodemetrically. Examination of the polymers by infraredspectroscopy shows that oxygenated groups are introduced on the polymerduring oxidation and are retained during reduction. No active oxygen inthe form of peroxides, hydroperoxides, or peracids is detected afterreduction by any of the preferred methods. The preferred oxidizedpolymer products contain from about 0.5 to about 10 weight percentoxygen.

The oxidized polymer is recovered from solution by ordinary methods,e.g., by steam distillation of the solvent or by precipitation with anacetone-methanol mixture (3:1) followed by drying in a vacuum.

The dewaxing aids of this invention comprise from about 1 to about 99percent by weight of the aforedescribed Friedel- Crafts condensationproduct and from about 1 to about 99 weight percent of theaforedescribed ethylene-alpha-olefin polymer. Particularly preferredproportions are admixtures comprising about 25 to about 75 weightpercent of the Friedel-Crafts condensation product and from about 25 tobout 75 weight percent of the ethylene-alpha-olefin polymer.

The synergistic dewaxing aid composition may be utilized in a number ofpetroleum dewaxing operations such as, for example, the conventionalsolvent dewaxing processes. It has been found that in these dewaxingoperations, the removal of precipitated wax from a petroleum oil can besubstantially improved by the incorporation of from about 0.001 to about5 weight percent, preferably 0.0] to about 1.0 weight percent (based onweight of wax-containing petroleum oil) of the dewaxing aid compositionprior to the precipitation of the wax from the said oil. While theproducts of the present invention may be utilized to separate wax from anumber of petroleum stocks such as residua, middle distillates and thelike, it has special application to waxy lubricating oil fractions.These fractions generally range in boiling point from about 400 to about900 F. and contain from about 5 to about 20 weight percent wax.

Various methods may be used to effect the blending of the synergisticdewaxing aid composition, the wax-containing oil, and the dewaxingsolvent, where used. For example, the dewaxing aid and thewax-containing petroleum oil may be combined prior to the addition of adewaxing solvent or alternately, the dewaxing solvent can be admixedwith the oil prior to the addition of the dewaxing aid. Broadly, anadmixing temperature of about to about 250 F. is used. It is preferred,however, that the temperature be from about to about 200 F.

The dewaxing aids of this invention are found compatible with otheradditive materials and may be blended successfully with petroleum oilscontaining minor amounts of viscosity index improvers, rust inhibitors,lubricity agents, oxidation inhibitors, and the like.

The invention can be more fully understood by reference to the followingexamples.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Example I An ethylene/propylenecopolymer having a number average molecular weight of about 15,000 andcontaining about 60 weight percent ethylene was prepared by reacting 6grams of ethylene with 4 grams of propylene in the presence of 1,000 ml.hexane at a temperature of about 25 C. and a pressure of about 1atmosphere for a period of about 1 hour. The foregoing polymerizationwas effected by using a Ziegler catalysts system consisting of 0.06grams of A]l(Et) C1 and 0.02 grams of VCI Fifty grams of the polymerizedproduct were accu mulated and then dissolved in 2 liters of n-heptaneand 0xidized by passing 200 ml. of oxygen gas (at 80 C. 750 mm. Hg)containing mg. of ozone per liter of oxygen through the solution. Thepressure was maintained at about 1 atmosphere and the temperature atabout 70 C. After 5 /2 hours of oxidation the polymer solution wascontacted for 1 hour with an equal volume of an aqueous solutioncontaining 5 weight percent sodium sulpltite. The polymer solution wasrecovered and washed with an equal volume of distilled water threetimes. The resultant oxidized polymer was recovered by steamdistillation of the n-heptane followed by vacuum drying at 40 C. forhours. Fifty grams ofa polymeric product containing l.2 weight percentoxygen (as determined by neutron activation) were recovered.

Example 2 The following example illustrates the synergistic effectbetween a conventional Friedel'Crafts condensate (i.e., a condensationproduct of4 moles of chlorinated 170 F. m.p. wax containing 12 weightpercent chlorine with 1 mole of naphthalene) and the oxidizedethylene-propylene product prepared in example 1.

In this example 0.02 weight percent (based on weight of wax-containingoil) of the above waxmaphthalene condensate and 0.02 weight percent(based on weight of wax-containing oil) of the oxidizedethylene/propylene copolymer prepared in example 1 were admixed at 145F. with a waxy lube oil having the properties shown in table I andhereinafter referred to as test oil.

TABLE I PROPERTIES OF TEST OIL* Baton Rouge bright stock from EastMississippi crude.

The above additive mixture-test oil blend was dewaxed in a conventionalsolvent dewaxing process, i.e., the additive-oil blend was dewaxed bydiluting with hexane at a hexane/oil ratio of 3.5/1 and then chilling atthe rate of 2 F. per minute from a feed temperature of 145 F. to afilter temperature of F. The chilled mixture was then continuouslyfiltered through a leaf filter at a pressure differential of 20 inchesof mercury. The filtration cycle consisted of a filtration time of 36seconds. a drying time of 9 seconds, a wash time of 27 seconds. and asecond drying time of 18 seconds.

Other samples of the test oil were dewaxed in the same manner as aboveexcept that 0.04 weight percent (based on weight of wax-containing oil)of each of the individual components of the dewaxing aid admixture wasadded to a separate oil sample prior to chilling. The feed mixturescomprising 0.04 weight percent of the individual dewaxing aids i.e.,wax-naphthalene condensate or the oxidized ethylenepropylene copolymer)were then separately processed under the same dewaxing conditions asused in the aforedescribed operation wherein the dewaxing aid admixturewas used.

The data obtained from the above respective dewaxing operations were asshown in table II.

TABLE II DEWAXING A WAXY LUBE OIL Filtration Oil rate. gall YieldDewaxing Aid Used hr. t't. 7:

None 7 0.04 wt. "/1 of wax-naphthalene condensate l4 B2 0.04 wt. /r ofoxidized copolymer 8 B2 0.04 wt. 71 of 50/50 mixture of waxnaphthalenecondensate/oxidized copolymer" 20 82 *Co olymer ofcthylene withropylene.

EXAMPLE 3 In another test, an ethylene-propyl-ene-methylene norborneneterpolymer comprising 68 weight percent ethylene and 4 weight percentmethylene norbornene and having a number average molecular weight ofabout 7,200 was prepared by essentially the same polymerizationconditions described in example l. The terpolymer was blended in thetest oil alone and in combination with the wax-naphthalene condensatedescribed in example 2. These oil-dewaxing aid blends were thenprocessed according to the solvent dewaxing operation described inexample 2. The comparative filtration rates for the oils containing noadditive, 0.04 weight percent of the wax-naphthalene condensate, 0.04weight percent of the ethylene-propylenemethylene norbomene terpolymer,and 0.04 weight percent (wt. percent are based on weight ofwaxcontaining oil) of an additive admixture containing equal amounts ofthe wax-naphthalene condensate and the ethylenepropylene-methylenenorbornene terpolymer are shown in table Ill.

None 7 80 0.04 wt. 71 of wax-naphthalene condensate 14 82 0.04 wt. k ofterpolymer' 8 81 0.04 wt. x? of 50/50 mixture of wax-naphthalenecondensnte/ terpolymer 23 82 Terpolymci' of ehtylene-propylene-methylcnenorhornene.

From the data in table 111, the synergistic effect provided by thecombination of the wax-naphthalene condensate with theethylene-propylene-methylene norbornene terpolymer is evident. Thus, thecombination of the additive components of the instant invention has, inthis example, imparted at least a 60 percent improvement over that whichcould be obtained by the use of an equivalent weight amount of eithermaterial alone.

Example 4 This example illustrates the preparation of an ethylene-Calpha-olefin copolymer, and the enhanced coaction between this copolymerand a conventional wax crystal modifier made by the Friedel-Craftscondensation reaction.

Four hundred and forty grams of C alpha-olefin, 10 grams of t-butylperoxide, 200 ml. of benzene and 2,000 pounds of ethylene gas pressurewere charged into a 3-liter stainless steel bomb, i.e., pressurereactor, and heated for 12 hours at 300 C. The unreacted monomer andsolvent were then removed'by distillation under vacuum. 670 grams of agreasy white polymer were recovered.

The above copolymer was blended in the aforedescribed test oil alone andin combination with the wax-naphthalene condensate described in example2. These oil-dewaxing aid blends were then processed according to thesolvent dewaxing operation described in example 2. The comparativefiltration rates for the oils containing no additive, 0.04 weightpercent of the wax-naphthalene condensate, 0.04 weight percent of theethylene-C alpha-olefin and 0.04 weight percent (weight percent arebased on weight of wax-containing oil) of an additive admixturecontaining equal amounts of the waxnapthalene condensate and theethylene C alpha-olefin polymer are shown in table 1V. it is again seenthat the incorporation of the additives of the instant inventionsynergistically improves the wax crystal characteristics of the oil.

TABLE IV DEWAXlNG A WAXY LUBE STOCK Filtration Rate Dewaxing Aid UsedgtiL/hrv ft.

None 5 0.04 \\'t. A of wax-naphthalene condensate 0.04 wt. ll of coolymer 0.04 wt. '7: of 50/50 mixture of wax-naphthalenecondemate/copolymer *Copolymer ofcthylene with C alpha-olefin,

It is not intended to restrict the present invention to the foregoingexamples, but rather it should be only limited by the appended claims.

We claim:

1. A dewaxing aid composition comprising a mixture of about 25 to 75weight percent of a pour depressing Friedel- Crafts condensation productof an aromatic hydrocarbon having a maximum of three substituent groupsand/or condensed rings and a halogenated paraffin having eight to 30carbon atoms and about 75 to 25 weight percent ofa copolymer comprisingabout 5 to mole percent of ethylene and C -C alpha-olefin, saidcopolymer having a molecular weight within the range of about 500 to50,000.

2 dewaxing aid composition comprising a mixture of about 25 to 75 weightpercent of a pour depressing Friedel- Crafts condensation product ofnaphthalene and a paraffin wax having melting point of to F. chlorinatedto contain 5 to 25 weight percent chlorine, and about 75 to 25 weightpercent of a copolymer comprising bout 5 to 95 mole percent ethylene andC C alpha-olefin, said copolymer having a molecular weight within therange of about 500 to 50,000.

3. A dewaxing aid composition comprising a major proportion of a waxcontaining petroleum oil and a wax modifying amount of a synergisticmixture of about 25 to 75 weight percent of a Friedel-Craftscondensation product of naphthalene and a paraffin wax having a meltingpoint of 120 to 190 F. chlorinated to contain 5 to 25 weight percentchlorine, and about 75 to 25 weight percent of a copolymer comprisingabout 5 to 95 mole percent ethylene and C -C alpha-olefin, saidcopolymer having a molecular weight within the range of about 500 to50,000.

4. A composition according to claim 3 wherein said copolymer has beenoxidized and then reduced.

5. A composition according to claim 3 wherein said alphaolefin containsfrom about 12 to about 24 carbon atoms.

6. A composition according to claim 3 wherein said alphaolefin ispropylene, said copolymer being oxidized and then reduced.

7. A composition according to claim 3 wherein said copolymer contains aC, ,C, nonconjugated diolefin present in a concentration of about 0.5 to20 mole percent based upon the total amount of ethylene and C -Calpha-olefin present.

8. A composition according to claim 7 wherein said diolefin is methylenenorbornene.

9. 1n the process for the separation of wax from petroleum oils by thesteps which include chilling the oil to form solid wax crystals andremoving said wax crystals; the improvement of incorporating into saidoil prior to formation of said wax crystals, a dewaxing aid comprising asynergistic mixture of about 25 to 75 weight percent of a Friedel-Craftscondensation product of naphthalene and a paraffin wax having a meltingpoint of 120 to 190 F. chlorinated to contain 5 to 25 weight percentchlorine, and about 75 to 25 weight percent of a copolymer comprisingabout 5 to 95 mole percent ethylene and C; to C alpha-olefin, saidcopolymer having a molecular weight of about 500 to 50,000.

000.
 2. A dewaxing aid composition comprising a mixture of about 25 to75 weight percent of a pour depressing Friedel-Crafts condensationproduct of naphthalene and a paraffin wax having melting point of 120*to 190F. chlorinated to contain 5 to 25 weight percent chlorine, andabout 75 to 25 weight percent of a copolymer comprising bout 5 to 95mole percent ethylene and C3-C30 alpha-olefin, said copolymer having amolecular weight within the range of about 500 to 50,000.
 3. A dewaxingaid composition comprising a major proportion of a wax containingpetroleum oil and a wax modifying amount of a synergistic mixture ofabout 25 to 75 weight percent of a Friedel-Crafts condensation productof naphthalene and a paraffin wax having a melting point of 120* to 190*F. chlorinated to contain 5 to 25 weight percent chlorine, and about 75to 25 weight percent of a copolymer comprising about 5 to 95 molepercent ethylene and C3-C30 alpha-olefin, said copolymer having amolecular weight within the range of about 500 to 50,000.
 4. Acomposition according to claim 3 wherein said copolymer has beenoxidized and then reduced.
 5. A composition according to claim 3 whereinsaid alpha-olefin contains from about 12 to about 24 carbon atoms.
 6. Acomposition according to claim 3 wherein said alpha-olefin is propylene,said copolymer being oxidized and then reduced.
 7. A compositionaccording to claim 3 wherein said copolymer contains a C10-C15nonconjugated diolefin present in a concentration of about 0.5 to 20mole percent based upon the total amount of ethylene and C3-C30alpha-olefin present.
 8. A composition according to claim 7 wherein saiddiolefin is methylene norbornene.
 9. In the process for the separationof wax from petroleum oils by the steps which include chilling the oilto form solid wax crystals and removing said wax crystals; theimprovement of incorporating into said oil prior to formation of saidwax crystals, a dewaxing aid comprising a synergistic mixture of about25 to 75 weight percent of a Friedel-Crafts condensation product ofnaphthalene and a paraffin wax having a melting point of 120* to 190* F.chlorinated to contain 5 to 25 weight percent chlorine, and about 75 to25 weight percent of a copolymer comprising about 5 to 95 mole percentethylene and C3 to C30 alpha-olefin, said copolymer having a molecularweight of about 500 to 50,000.